The present invention relates to a shelf support of the type which is elongate and is for extending along a substantial part of the rear of a rectangular-section shelf and holding it as a cantilever, this type of shelf support having a rigid support member upon which the underside of the rear part of the shelf will rest, a rigid retaining member for retaining the top of the rear part of the shelf, and a rigid member which interconnects the support and retaining members, whereby the shelf support can be fixed to a vertical wall and thereby mount the shelf on the wall.
U.S. Pat. No. 4,508,301 discloses such a shelf support, and in practice such shelf supports have had considerable commercial success. U.S. Pat. No. 4,508,301 also discloses that an insert can be placed under the retaining member in order to hold shelves of reduced thickness, but the insert used is a rigid insert. It is understood that no materials are absolutely rigid, and indeed the shelf support of U.S. Pat. No. 4,508,301 and some embodiments of the shelf support of the present invention do rely on some elastic distortion of the retaining member or interconnecting member; however, in a general sense, the support member, retaining member and interconnecting members are rigid.
The shelf support of U.S. Pat. No. 4,508,301 has given some problems when supporting glass shelves. The force necessary to insert the shelf may cause some chipping or breakage of the glass.
U.S. Pat. No. 2,477,771 discloses a shelf support which is not of the cantilever type and which does not extend along a substantial part of the rear of the shelf, not being elongate. However, the problem of supporting and suitably clamping glass shelves is considered and is solved using a normal shelf bracket at each end of the glass shelf but with resilient fingers which engage the top of the rear part of the shelf and a ramp on the top of the rear part of the bracket which causes the glass shelf to rise as it is pushed home and to push the resilient finger upwards. This arrangement is not easy to fabricate and assemble and the use of resilient fingers would give problems when applied to an elongate shelf support; the fingers would have to be in the form of an upper flange which would have to be of sufficiently low resilience to enable the glass shelf to be pushed home without difficulty.
Before making the present invention, the inventors were aware of an extruded shelf support of said type where however the front portion of the support member had an undercut groove in its upper side with a flexible insert held in the groove and forming an arcuate bulge at the very front of the upper side of the support surface. This shelf support is for normal shelves of say 15 mm thickness and is not for glass shelves. The insert does not reduce the force required for insertion.
The Invention
According to the invention, the retaining member carries an elastically-deformable member which will engage the top side of the rear part of the shelf and elastically deforms when the shelf is in position, the elastically-deformable member being a strip which runs along the bottom of the retaining member.
The use of the elastically-deformable strip enables a glass shelf to be retained without marked risk of damaging the shelf. Specifically, the shelf support prevents easy removal of the shelf--easy removal is highly undesirable as it can permit accidental dislodgement. The elastically-deformable member is substantially spaced behind the front of the support member and this gives firm retention and little elastic movement of the shelf if its front edge is pulled down. The shelf does not tend to ride out of the shelf-receiving slot.
The shelf support can be manufactured of just two components, and is simple in fabrication and assembly. Both components can be formed as extrusions; the support member, retaining member and interconnecting member can be formed as an integral unit as for instance an aluminium extrusion; the elastically-deformable member can be formed as an extrusion of an elastomer such as rubber or a suitable plastics material.
Although some slight flexing of the retaining member can occur with respect to the support member, in substance all the distortion that occurs when inserting the shelf occurs in the elastically-deformable member.
However, the use of an elastically-deformable strip as such gives problems in that the strip tends to be pushed back and bunched up when the shelf is pushed home. In order to avoid this, the strip may, as seen in vertical cross-section, comprise a main part having at least one downwards protuberance which is substantially narrower (front to rear) than the main part. The downwards protuberance is more easily deformed than the main strip and does not apply enough force to the main strip to cause the main strip as a whole to be pushed right back (although the main strip will move back to some extent in normal circumstances). In this way, a firm and secure mounting can be provided for a glass shelf. In addition, when the shelf is under load and tends to tip forwards, the main part offers greater resistance than the protuberance and this limits the tipping movement.
There is an incidental advantage. Such shelf supports are normally fixed to the vertical wall by using screws which are located at the rear of the slot which receives the rear part of the shelf. Shelves such as glass shelves are relatively thin, and thus the slot will be thin. By using the elastically-deformable strip, the screws can have heads whose diameter is just slightly less than the distance between the rigid retaining member and the rigid support member, and a full-width screw-driver can be used to screw the screw home; the screw-driver will distort the strip, but this distortion is mainly elastic and does not matter in practice.
It is an advantage that the width (front to rear) or depth (top to bottom) of the protuberance can be increased or decreased in order to alter the compression on the shelf. It is also considered that the use of the relatively thin protuberances gives better grip where, as is preferred, the protuberance or one of the protuberances is beneath the front part of the retaining member, and if the shelf is first of all put in position with its front edge raised, the top rear edge of the shelf engages towards the rear of the protuberance, or actually behind the protuberance; this helps avoid pushing the protuberance and hence the whole strip backwards with the leading edge of the shelf. When the shelf is in position, this front protuberance grips the shelf and also stops the front of the shelf being lifted up.
If, as is preferred, there is a protuberance which is intermediate the front and the rear of the retaining member, this protuberance is able to resist being pushed backwards as the shelf is pushed home, particularly if the strip is retained at a position between its front and rear. This middle protuberance acts mainly to grip the shelf when the shelf is in position. Also, while the shelf is being pushed home, the middle protuberance keeps the rear edge of the shelf down and stops the rear edge jamming against the rear protuberance, if there is a rear protuberance. The middle protuberance is preferably narrower than the front protuberance in order to enable the shelf to slide more easily under the middle protuberance.
The rear protuberance, if present, acts to grip the shelf when it is in position, and also stops the shelf front tipping down. The rear protuberance is narrower than the middle or front protuberances (if present) so that the shelf slides more easily under the rear protuberance.
In a useful construction, the retaining member comprises (as seen in vertical section) a first, top, forwardly and downwardly inclined part whose top, rear end is arranged to abut or nearly abut the vertical wall to give bracing, a second, forwardly and upwardly inclined part connected to the interconnecting member and joining the first part intermediate its length a horizontal lip extending rearwards from the front, lower end of the first part, and a horizontal lip extending forwards from the rear, lower end of the second part, the lips defining therebetween a slot which receives part of the elastically-deformable member in order to retain the elastically-deformable member in position. The lower portion of the first part, the second part and the two lips form a generally triangular shape, and provide a good, sufficiently rigid construction.
The dip shown in the support surface of the shelf support of U.S. Pat. No. 4,508,301 can be provided, but is not essential. Although the shelf support was designed for use with glass shelves, the shelf may for instance be formed of plywood or perspex.